What a great find. I like the other name the movie is known by much better, "Assignment In China".
This is a well told story about a former Marine whose missionary parents were murdered in Mongolia. He joins the foreign service and is assigned to a small outpost Counsel in Mongolia to try and get information about a warlord.
To enjoy this movie you have to remember what was going on in China in 1949 when the movie was made. Americans in unstable China have been the background for a number of really good movies,,i.e. 55 Days At Peking and the Sand Pebbles. While this movie is not in the same class as those 2 movies, the plot compares quite favorably.
There really was and is a American Foreign Service Memorial Plaque. The first was dedicated in 1933 and a second was added in 1972. They have a total of around 236 names as of May, 2012.
The well shot film is in color. The acting was well done. I am glad that I overlooked the prior ratings and looked for myself. I wonder how many other gems are buried in this site?

It's an okay movie about a guy that grew up in China but doesn't know a lot about China. He becomes a secret agent for the US and goes back to spy. Then there's some aimless action and dialoque, then suddenly the movie is over.

Just from the review above I'll have a look, I thought this was in the wrong place. I didn't know it was a film. So where's the other 648 files.

This is the first film from the brothers Neufeld/Newfield after the buy-out of PRC by Eagle-Lion in 1948. Only the second Neufeld production in color (Cinecolor). This is a pristine print with sharpness and good color and sound from who knows where, since most TV prints and DVDs of this film are in B/W.
Beyond that, this a very slowly moving film based on events happening in China at the time and could only have been financed by the American government, if not directly, then indirectly through nefarious channels. The best clue to that is the producer wasn't known to waste a penny. Color, minatures, special effects, location second-unit filming in Washington just not his style. But, it's propaganda film none the less, which was obsolete 6 months into 1949 and ancient history by June 1950. The flag waving is low key, but it pushes all the right buttons.
William Lundigan is fine in a low key way. Virginia Bruce as his required love interest is not only showing her age, but brings a worldly approach to her part. The best and most noteworthy actress in the film is Barbara Woodell, a fine player whose later work is very well known. The many, many unbilled young men in the cast are a great guessing game of who is or who became who. No hints from me. The Asian stereo-types are all here too in their most famous personages.
A film buff's, with some patience, delight. Otherwise curiosity value only.